The present invention concerns a sealing assembly for a rolling element bearing.
In particular, the assembly according to the present invention, as well as being capable of protecting the rolling bodies of the bearing from external contaminants and, at the same time, keeping the lubricating grease within the bearing, includes a signalling element capable of co-operating with a detector device outside the assembly; the assembly formed by the signalling device and the detector device enables the detection of the speed of rotation of the moving element of the bearing and/or a mechanical member possibly fixed thereto such as, for example, the wheel of a vehicle.
Assemblies of the type described above are known, in which the signalling element is a phonic wheel formed from magnetic material and integrated in the protective seal of the bearing; specifically, the phonic wheel is fixed to the rotating ring of the bearing and coupled with a fixed sensor connected, for example, to the fixed ring of the bearing.
Problems of positioning and fixing to the associated suspension strut may be encountered with sealing assemblies formed in this way. In fact, one of the two bearing rings is usually abutted against a shoulder on the strut, while a further shoulder is formed by a resilient ring fitted on the strut itself. However, due to the typical tolerances and errors in manufacturing processes, the dimensions of the bearing may not coincide perfectly with the space provided for its mounting; play may therefore be present between the bearing itself and the shoulders after mounting, which causes vibrations and therefore noise when the vehicle is operating.